Field of the Invention
The present invention relates to basket type grasping forceps.
Description of the Related Art
In the related art, basket type grasping forceps inserted into a duct line in a body such as a bile duct or the like and configured to collect foreign substances such as calculi or the like are known (for example, see Japanese Unexamined Patent Application, First Publication No. H11-114070, Japanese Unexamined Patent Application, First Publication No. 2006-94876, and PCT International Publication No. 2012/141213).
Since the basket type grasping forceps have a structure configured to hold foreign substances by a plurality of wires, when large foreign substances are to be collected, a basket may not be removed from the duct line while holding the foreign substances. In this case, the temporarily held foreign substances should be discharged from the basket in the duct line even to only remove the basket type grasping forceps. However, in such a case, since the foreign substances are large, once the foreign substances are held, the foreign substances may not be discharged to the outside of the basket in the duct line as an operator intends. For example, when the foreign substances are not removed from between the plurality of wires disclosed in Japanese Unexamined Patent Application, First Publication No. H11-114070, Japanese Unexamined Patent Application, First Publication No. 2006-94876, and PCT International Publication No. 2012/141213, the basket cannot be removed from the duct line.
Furthermore, when an excessive load is applied to the plurality of wires that constitute the basket, a portion at which the plurality of wires are bundled may be damaged and break the basket. Japanese Unexamined Utility Model Application, First Publication No. H02-116411 discloses a structure in which, as one of the plurality of wires is formed in a hook shape and is hooked to a manipulation wire for advancing and retracting the basket, the basket can be prevented from being completely removed and falling off from the manipulation wire when a proximal end of the basket is broken.